Nidifugous in the context of Wader

Konrad Zacharias Lorenz (Austrian German pronunciation: [ˈkɔnʁaːd tsaxaˈʁiːas ˈloːʁɛnts] ; 7 November 1903 – 27 February 1989) was an Austrian zoologist, ethologist, and ornithologist. He shared the 1973 Nobel Prize in Physiology or Medicine with Nikolaas Tinbergen and Karl von Frisch. He is often regarded as one of the founders of modern ethology, the study of animal behavior. He developed an approach that began with an earlier generation, including his teacher Oskar Heinroth.

Lorenz studied instinctive behavior in animals, especially in greylag geese and jackdaws. Working with geese, he investigated the principle of imprinting, the process by which some nidifugous birds (i.e. birds that leave their nest early) bond instinctively with the first moving object that they see within the first hours of hatching. Although Lorenz did not discover the topic, he became widely known for his descriptions of imprinting as an instinctive bond. In 1936, he met Tinbergen, and the two collaborated in developing ethology as a separate sub-discipline of biology. A Review of General Psychology survey, published in 2002, ranked Lorenz the 65th most cited scholar of the 20th century in the technical psychology journals, introductory psychology textbooks, and survey responses.

Precocial (/prɪˈkəʊʃəl/) species in birds and mammals are those in which the young are relatively mature and mobile from the moment of birth or hatching. They are normally nidifugous, meaning that they leave the nest shortly after birth or hatching. Altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. These categories form a continuum, without distinct gaps between them.

In fish, this often refers to the presence or absence of a stomach: precocial larvae have one at the onset of first feeding whereas altricial fish do not. Depending on the species, the larvae may develop a functional stomach during metamorphosis (gastric) or remain stomachless (agastric).